Respiratory
Wheezing
A high-pitched whistling sound when breathing, usually as air moves through narrowed airways.
Education and reference only. This explains the common causes of wheezing and the warning signs that need urgent help, in plain language — it is not a diagnosis or a substitute for advice from a clinician. If you feel very unwell or are worried, seek medical help.
Quick answer
What is wheezing?
Wheezing is a whistling or squeaky sound, usually heard as you breathe out, caused by air being forced through narrowed or tightened airways. It is often linked to conditions like asthma or long-standing lung disease, where the airways are sensitive and prone to narrowing.
- Get urgent help: Severe breathlessness, being unable to speak in full sentences, or blue lips – call 999. Wheezing with swelling of the lips, face or throat, or after an insect sting or new food or medicine – this is ANAPHYLAXIS; call 999.
- Self-care: If you already have a diagnosis such as asthma, the most important self-care is to use your prescribed inhalers as advised and follow your personal action plan if you have one.
About wheezing
Wheezing is a whistling or squeaky sound, usually heard as you breathe out, caused by air being forced through narrowed or tightened airways. It is often linked to conditions like asthma or long-standing lung disease, where the airways are sensitive and prone to narrowing. Wheezing can come and go, be triggered by colds, exercise, allergens or cold air, and may come with a cough, chest tightness or breathlessness. While many causes are manageable, severe breathlessness, an inability to speak in full sentences, or wheezing with swelling of the lips or throat are emergencies. Noticing what triggers it and how breathless it makes you helps judge how serious it is.
When to get help
Call 999 or go to A&E if wheezing comes with any of these warning signs:
- Severe breathlessness, being unable to speak in full sentences, or blue lips – call 999.
- Wheezing with swelling of the lips, face or throat, or after an insect sting or new food or medicine – this is ANAPHYLAXIS; call 999.
- A sudden first-ever wheeze with choking – a possible inhaled object.
When to see a doctor
See a doctor if you develop a wheeze for the first time, or if your usual wheezing is becoming more frequent, waking you at night, or not responding as well to your treatment. It is worth being reviewed if a chest infection is making your breathing worse, or if wheezing is limiting what you can do day to day. If you have asthma or another lung condition, regular reviews help keep your treatment right and reduce flare-ups.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
What can cause it
Common causes of wheezing
Wheezing has many possible causes. Each links to a full, plain-language guide to that condition — what it is, how it's treated and when to seek help.
What helps
Self-care and what you can do
If you already have a diagnosis such as asthma, the most important self-care is to use your prescribed inhalers as advised and follow your personal action plan if you have one. Avoiding known triggers, not smoking and steering clear of smoky or polluted air can reduce how often you wheeze. Staying calm and sitting upright can make breathing feel easier during a mild episode. Keep your reliever inhaler with you, and never ignore a wheeze that is not easing with your usual treatment, as this is a sign to seek help promptly.
Answers
Wheezing: frequently asked questions
When is wheezing a medical emergency?
Call 999 if you are severely breathless, cannot speak in full sentences, or your lips look blue. Wheezing with swelling of the lips, face or throat, especially after a sting or new food or medicine, is anaphylaxis and also needs an emergency 999 call.
What usually causes wheezing?
Wheezing happens when air moves through narrowed airways, often due to asthma, long-standing lung disease, or a chest infection. Triggers can include colds, exercise, allergens and cold air. A new or worsening wheeze should be assessed to find the cause.
I have asthma and I am wheezing – what should I do?
Use your reliever inhaler as advised and follow your personal asthma action plan. Sit upright and try to stay calm. If your symptoms are not easing, you need your reliever more and more, or you are becoming breathless, seek urgent help rather than waiting.
Can a chest infection cause wheezing?
Yes. Infections can inflame and temporarily narrow the airways, leading to a wheeze and cough that usually settle as you recover. If breathing becomes difficult, the wheeze is severe, or you feel very unwell, get medical help promptly.
Sources
Where this is drawn from
- NICE CKS: Asthma.
- Asthma + Lung UK.
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